diff --git a/src/datetime.js b/src/datetime.js
index 0958787a..1a98f2a8 100644
--- a/src/datetime.js
+++ b/src/datetime.js
@@ -513,7 +513,7 @@ export default class DateTime {
   /**
    * @access private
    */
-  constructor(config) {
+  constructor(config = {}) {
     const zone = config.zone || Settings.defaultZone;
 
     let invalid =
diff --git a/src/duration.js b/src/duration.js
index c1135def..77ce80dc 100644
--- a/src/duration.js
+++ b/src/duration.js
@@ -217,7 +217,7 @@ export default class Duration {
   /**
    * @private
    */
-  constructor(config) {
+  constructor(config = {}) {
     const accurate = config.conversionAccuracy === "longterm" || false;
     let matrix = accurate ? accurateMatrix : casualMatrix;
 
diff --git a/src/interval.js b/src/interval.js
index 6073d028..088da66b 100644
--- a/src/interval.js
+++ b/src/interval.js
@@ -40,7 +40,7 @@ export default class Interval {
   /**
    * @private
    */
-  constructor(config) {
+  constructor(config = {}) {
     /**
      * @access private
      */
diff --git a/test/datetime/create.test.js b/test/datetime/create.test.js
index 67613a61..7f3d3836 100644
--- a/test/datetime/create.test.js
+++ b/test/datetime/create.test.js
@@ -9,6 +9,13 @@ const withDefaultLocale = Helpers.withDefaultLocale,
   withthrowOnInvalid = Helpers.setUnset("throwOnInvalid"),
   withDefaultZone = Helpers.withDefaultZone;
 
+//------
+// new
+//------
+test("Default constructor works", () => {
+  expect(() => new DateTime()).not.toThrow();
+});
+
 //------
 // .now()
 //------
diff --git a/test/duration/create.test.js b/test/duration/create.test.js
index 1a6cbb22..0f355c07 100644
--- a/test/duration/create.test.js
+++ b/test/duration/create.test.js
@@ -2,6 +2,13 @@
 
 import { Duration } from "../../src/luxon";
 
+//------
+// new
+//------
+test("Default constructor works", () => {
+  expect(() => new Duration()).not.toThrow();
+});
+
 //------
 // .fromObject()
 //-------
diff --git a/test/interval/create.test.js b/test/interval/create.test.js
index bab2a75e..056fab3c 100644
--- a/test/interval/create.test.js
+++ b/test/interval/create.test.js
@@ -4,6 +4,13 @@ import Helpers from "../helpers";
 
 const withThrowOnInvalid = Helpers.setUnset("throwOnInvalid");
 
+//------
+// new
+//------
+test("Default constructor works", () => {
+  expect(() => new Interval()).not.toThrow();
+});
+
 //------
 // .fromObject()
 //-------